1. Field of the Invention
The present invention relates to a video tape recorder (VTR) with a video printing controller, and more particularly to such a VTR which is capable of providing a video signal representing a specified image for printing the image in a hard copy by a printer.
2. Description of the Prior Art
Recently, the spread of video cameras and the progress in technology relating to video tape recorders (hereinafter abbreviated to "VTR") have made possible the recording of high-quality images and the reproduction of the recorded images in clear color pictures, and a color printer capable of printing an image represented by an image signal recorded by the VTR in a hard copy is in the initial stage of practical application. Such progress in video signal processing technology makes possible the reproduction of image information taken by a video camera and recorded by the VTR in a hard copy similar to a photographic print.
Image signals recorded by the VTR can be printed by a color printer or the like by the following methods.
(1) Images recorded on a magnetic tape by the VTR are reproduced and a desired image to be printed, among those being continuously and serially displayed on a monitor TV set, is selected by operating a color printer connected to the image signal output terminal of the VTR. The printer stores the image signal representing the desired image when the desired image is displayed on the monitor TV set and prints the image signal in a hard copy.
(2) Image signals recorded on a magnetic tape by the VTR are simultaneously reproduced and displayed on a monitor TV set. The VTR is commanded to pause when a desired image is displayed on the monitor TV set to hold the image still, and a color printer connected to the image signal output terminal of the VTR is operated to print the desired image in a hard copy.
The method of (1) has the problem that the desired image cannot be printed with certainty unless the color printer is operated at the proper moment, because the image signal representing the desired image must be transferred to the color printer during the active reproduction of images, i.e. while the magnetic tape is being transported through the VTR.
The method of (2) is able to print a particular desired image without fail because the video signal representing the desired image is given to the color printer while the VTR is in the pause mode. However, the quality of the image, in general, is deteriorated when the VTR is paused and hence it is impossible to obtain a clear color print.
In an 8 mm video recording system, an index signal is added to a postamble area in each recording track in a mode in which video signals and audio signals are recorded simultaneously as PCM data. The index signals are used for cue searching. However, some simple 8 mm VTRs are not equipped with a PCM recording function and such simple 8 mm VTRs are not provided originally with any fixed head. Therefore, such simple 8 mm VTRs are unable to locate cues for recorded video signals, and hence such a simple 8 mm VTR takes a long time to search for a desired video signal and to print an image represented by that desired video signal.
Accordingly, it is an object of the present invention to provide a VTR with a video printing controller, capable of adding marker signals to skewed video tracks of a magnetic tape at predetermined positions during recording or reproducing operations, detecting the marker signals through a cue search operation, and enabling the reproduction of images recorded in a desired video track after detecting the marker signal.
The VTR is connected to a color printer by bilateral (two) bus lines so that when the video signal specified by the marker signal is provided in the reproducing mode the video signal is transferred to the field memory of the color printer and the color printer is actuated for printing the video signal. Thus, an optional image can easily be selected through a simple operation and the selected image can be printed in a clear color print.
In an 8 mm VTR according to the present invention, a portion of the skewed video track corresponding, for example, to a V-P guard space is detected by a counting circuit which counts clock signals on the basis of a vertical synchronizing signal, and a marker of a predetermined format is recorded in portions of several tracks corresponding to the V-P guard space.
Ordinarily, in the simple 8 mm VTR, the angle of contact of the magnetic tape on the rotary drum is slightly greater than 180.degree., and a part of the V-P guard space of the skewed track of an 8 mm recording format engages the rotary drum first, and hence part of the V-P guard space is available for use as a recording area. Accordingly, when the recording area passes the rotary head in the recording mode, a predetermined marker signal is recorded in the recording area by the rotary head to add a mark for identifying a track in which the desired video signal is recorded, thereby enabling the marked video signal to be found in the search mode.